1. Field of the Invention
The present invention relates to an out-door unit, and more particularly, to an out-door unit with multiple ports.
2. Description of the Related Art
An out-door unit (ODU) is a wireless communication transceiver apparatus, such as a wireless communication transceiver apparatus applied to satellite communication, installed outdoors. A typical ODU applied to satellite communication comprises a low noise block (LNB) to process and convert a high frequency signal broadcasted by a satellite to an intermediate frequency signal for used by an in-door unit (IDU), such as a setup box, to receive a signal.
Power is supplied to an ODU by the IDUs to which it is connected with multiple ports. FIG. 1 shows a conventional ODU with multiple ports. As shown in FIG. 1, the ODU 100 is connected to a plurality of IDUs 11 to 14 and comprises a plurality of ports 101 to 104, a plurality of low noise amplifiers 111 to 114, a plurality of local oscillators 121 to 122, a plurality of mixers 131 to 134, a plurality of front-end intermediate frequency amplifiers 141 to 144, a plurality of switches 151 and 152 and a plurality of back-end intermediate frequency amplifiers 161 to 164. The plurality of low noise amplifiers 111 to 114 is configured to amplify received vertical and horizontal high-frequency satellite signals. The plurality of local oscillators 121 to 122 is configured to generate a plurality of intermediate frequency signals. The plurality of mixers 131 to 134 is configured to convert the received high-frequency satellite signals to a plurality intermediate frequency satellite signals by using the plurality of intermediate frequency signals. The plurality of front-end intermediate frequency amplifiers 141 to 144 is configured to amplify these intermediate frequency satellite signals and provide the amplified intermediate frequency satellite signals to the input terminals of the plurality of switches 151 and 152. The plurality of back-end intermediate frequency amplifiers 161 to 164 is configured to amplify the intermediate frequency satellite signals outputted by the plurality of switches 151 and 152 and provided to the plurality of IDUs 11 to 14 via the plurality of ports 101 to 104.
FIG. 2 shows a power supply network of the ODU with multiple ports shown in FIG. 1. The ODU 100 further comprises a plurality of voltage regulators 201 to 204 and a plurality of diodes 211 to 214. The plurality of voltage regulators 201 to 204 is configured to regulate the power provided by the plurality of IDUs 11 to 14 such that stable currents can be provided to the plurality of back-end intermediate frequency amplifiers. In addition, the plurality of voltage regulators 201 to 204 can provide stable currents via the plurality of diodes 211 to 214 to the plurality of low noise amplifiers 111 to 114, the plurality of local oscillators 121 to 122, the plurality of mixers 131 to 134, and the plurality of front-end intermediate frequency amplifiers 141 to 144 in a current-sharing configuration.
However, the power supply network shown in FIG. 2 requires too much power to meet the requirements of the industry. To reduce power consumption, adjustments can be made to the power supply network shown in FIG. 2. FIG. 3 shows a part of another power supply network of the ODU with multiple ports shown in FIG. 1. As shown in FIG. 3, the ODU 100 further comprises a plurality of diodes 301 to 304. The plurality of voltage regulators 201 to 204 shown in FIG. 2 can be combined to become a DC-DC converter 311. The power provided by the plurality of IDUs 11 to 14 is sent to the DC-DC converter 311, which then provides power to other devices, via the plurality of diodes 301 to 304 in a current-sharing configuration. The DC-DC converter 311 replaces the plurality of voltage regulators 201 to 204 to reduce the output voltage and thus reduce the total power consumption.
However, many of the IDUs require minimum supply currents. When power is supplied in a current-sharing configuration, and the provided voltages of the plurality of IDUs are different, e.g. the provided voltage of the IDU 11 is different from that of the IDU 12, one of the IDUs does not provide current, which does not meet the requirements of the industry.
To meet the minimum supply currents requirement, adjustments can be made to the power supply network shown in FIG. 3. FIG. 4 shows a part of another power supply network of the ODU with multiple ports shown in FIG. 1. As shown in FIG. 4, the ODU 100 further comprises a plurality of resistors 401 to 404. The plurality of resistors 401 to 404 are connected to the power providing paths of the plurality of IDUs 11 to 14 respectively such that the minimum supply current requirement of each of the plurality of IDUs 11 to 14 is met. However, the additional resistors 401 to 404 will increase the total power consumption.
FIG. 5 shows a part of another power supply network of the ODU with multiple ports shown in FIG. 1. As shown in FIG. 5, the plurality of back-end intermediate frequency amplifiers 161 to 164 are re-connected at the current supplying paths of the plurality of IDUs 11 to 14. Accordingly, the plurality of IDUs 11 to 14 provides the required current to the plurality of back-end intermediate frequency amplifiers to meet the minimum supply currents requirements. However, since the currents required by the plurality of back-end intermediate frequency amplifiers 161 to 164 are much higher than the minimum supply currents required by the plurality of IDUs 11 to 14, the total power consumption will increase.
In addition, each of the current supplying paths shown in FIGS. 4 and 5 can be serially connected with a DC-DC converter to reduce the current consumption of the plurality of resistors 401 to 404 and the plurality of back-end intermediate frequency amplifiers 161 to 164. However, the additional DC-DC converters will greatly increase the hardware costs.
Therefore, there is a need for an ODU with multiple ports, which can meet the minimum supply currents of IDUs and thus has the advantages of low power consumption and low hardware costs at the same time.